need help with noise problem Options

[LewFX]

theres this noise that happens when im driving, sorta like a bottle cap in the car somewhere rattling around, it mainly comes from the rear of the car. I just had my right rear bearings done, dunno if they went bad or what. this noise can get loud at times and other times soft. its almost like when you put a baseball card in your bike tire. has anyone else experienced this problem? or might know what can be causing it? im sick of taking it to a mechanic and they dont know what the problem is.